Abstract:
:A study of the concentrations of the common breath metabolites ammonia, acetone, isoprene, ethanol and acetaldehyde in the breath of five subjects over a period of 30 days has been carried out. Breath samples were taken and analysed in the early morning on arrival at the laboratory. The real time analyses of three consecutive breath exhalations were carried out using selected ion flow tube mass spectrometry (SIFT-MS) on line to the instrument. Sufficient data were obtained to allow meaningful concentration distributions to be obtained for ammonia, acetone, isoprene and ethanol. These showed that the ammonia, acetone and isoprene concentrations exhibited sensibly normal distributions, with coefficients of variation of typically 0.3. Obvious and statistically significant (p < 0.01) differences are apparent in the mean concentrations of these metabolites between the five individuals. The acetaldehyde concentrations were relatively low and close to the instrument detection limit, and the differences between the mean concentrations of the five subjects were not statistically significant (p = 0.4), so distributions were not obtained. The mean concentrations, in parts per billion (ppb), of each metabolite range amongst the five subjects are as follows: ammonia, 422-2389: acetone, 293-870; isoprene, 55-121; ethanol, 27-153; acetaldehyde, 2-5. There are no obvious patterns in the distributions of these particular metabolites for these individuals, except that the ammonia levels were greatest in the breath of the two oldest subjects.
journal_name
Physiol Measjournal_title
Physiological measurementauthors
Diskin AM,Spanel P,Smith Ddoi
10.1088/0967-3334/24/1/308subject
Has Abstractpub_date
2003-02-01 00:00:00pages
107-19issue
1eissn
0967-3334issn
1361-6579journal_volume
24pub_type
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